In the semiconductor industry, devices are fabricated by a number of manufacturing processes producing structures of an ever-decreasing size. Some manufacturing processes such as plasma etch and plasma clean processes expose a substrate to a high energy plasma combined with a mixture of corrosive gases to etch or clean the substrate. The plasma may be highly corrosive, and may corrode processing chambers and other surfaces that are exposed to the plasma. This corrosion may generate particles, which frequently contaminate the substrate that is being processed, contributing to device defects.
As device geometries shrink, susceptibility to defects increases, and particle contaminant requirements become more stringent. Accordingly, as device geometries shrink, allowable levels of particle contamination may be reduced. To minimize particle contamination introduced by plasma etch and/or plasma clean processes, chamber materials have been developed that are resistant to plasmas. Different materials provide different material properties, such as plasma resistance, rigidity, flexural strength, thermal shock resistance, machining flexibility, and so on. Also, different materials have different material costs. Accordingly, some materials have superior plasma resistance, other materials have lower costs, and still other materials have superior flexural strength and/or thermal shock resistance. Also, some materials (e.g., some yttria based ceramic materials) show good plasma erosion resistivity but bad machining flexibility and bad electrical conductivity, whereas other materials (e.g., aluminum) show the bad plasma erosion resistivity but good machining flexibility and good electrical conductivity.